In the 8M Mini datasheet, it specifically says that the 8M Mini must be supplied by an external RTC oscillator, *not* by a crystal. However, Boundary Devices is currently selling an 8M Mini SOM that uses a 32kHz crystal. The Nitrogen8M_Mini SOM uses crystal P/N OM-7604-C7 connected to RTC_XTALI and a 220 ohm resistor going from RTC_XTALO to VDD_SNVS_P8V. Please see attached image for view of the relevant schematic.
Is this another acceptable way to provide an RTC clock to the 8M Mini processor? If so, can you provide reccommended crystal parameters to use?